1. Field
This document relates to a stereoscopic image display device and a driving method thereof.
2. Related Art
Stereoscopic image display devices implement stereoscopic images, that is, three-dimensional (3D) images using a stereoscopic technique and an autostereoscopic technique. The stereoscopic technique uses binocular parallax images which are great in the stereoscopic effect, and may have a type of using glasses and a type of not using glasses. In the type of using glasses (“glass type”), binocular parallax images are displayed on a direct view display panel or a projector by changing polarization directions or in the temporal division manner, and polarization glasses or liquid crystal shutter glasses are used to implement stereoscopic images. In the type of not using glasses (“glassless type”), the stereoscopic images are implemented by dividing optical axes of binocular parallax images, by using optical plates such as parallax barriers provided at front and rear surfaces of a display panel.
As an example of the glass type, there is a stereoscopic image display device where a patterned retarder is disposed on the display panel. The stereoscopic image display device implements 3D images by using polarization characteristics of the patterned retarder and polarization characteristics of polarization glasses which a user wears, and has excellent image quality as compared with other stereoscopic image implementation methods in that crosstalk in the left eye and the right eye is little and the brightness is good at the time of implementation of the 3D images.
However, the stereoscopic image display device using the patterned retarder has disadvantages in that it has lower brightness for two-dimensional (2D) images, up and down viewing angles smaller at the 3D images, and lower resolution by 50% or so than a typical 2D dedicated display device.
For example, the patterned retarder transmits only first polarization light rays of light rays for left eye images output from odd numbered display lines, whereas it transmits only second polarization light rays of light rays for right eye images output from even numbered display lines output. A user wearing the polarization glasses can view the first polarization light rays for left eye images displayed in the odd numbered lines through a left eye polarization filter of the polarization glasses and can view the second polarization light rays for right eye images displayed in even numbered lines through a right eye polarization filter thereof. Thus, as shown in FIG. 1, during an N-th (where N is a positive integer) frame period, if left eye images of 3D images are displayed in the odd numbered display lines LINE#1 and LINE#3 of the display panel and, during a (N+1)-th frame period, right eye images of the 3D images are displayed in the even numbered display lines LINE#2 and LINE#4, the user alternately views the left eye images and the right eye images of the 3D images at a half resolution as compared with the resolution of the display panel.